Artemisia plants grow in many parts of the world, and many varieties have long been known to have medicinal properties. One particular variety, Artemisia annua L., sometimes known as annual wormwood (or sweet sagewort) contains a drug recognized as one of the most effective anti-malaria medications. The World Health Organization is encouraging farmers to produce more of the plants. VOA's Zulima Palacio has more in this story, narrated by Barry Wood.

Artemisia, growing in Arusha, Tanzania, among other places, has been used in Chinese traditional medicine for centuries, and is known as Qinghao. It is now in great demand for its malaria-fighting properties – especially the ability to attack malaria that is resistant to all other medication.

The World Health Organization recognizes Artemisia's special properties, and has issued guidelines for cultivating the plant and harvesting its medicinal ingredient. The U.N. agency is trying to ensure a sustainable supply of the drug artemisinin to meet growing demand.

Enough artemisinin-based anti-malarial therapies have been produced to help more than 80 million people, but WHO estimates that 600 million people need the medicine. Most who suffer from drug-resistant malaria live in Africa, often in impoverished areas.

At Cameroon's University of Yaounde, Professor Wilfred Mbacham worries that artemisinin shortages could lead to counterfeiting.

"If the artemisinin should run short in supply of that active ingredient, then we're bound to see counterfeiting,” he says. “Now there have been talks on whether to synthetically manufacture the active ingredient. I think we will see an increase in the level of concern for producing the raw material, not only in Asia but also in other parts of Africa."

The quantity and quality of artemisinin that an Artemisia plant produces can vary greatly, according to climate, geography and other factors.

These plants are young, but in six months they will grow to their full height, two meters. WHO says soil quality, temperature and rainfall have a big effect on whether a plant produces high-quality artemisinin.

ASAQ is the most promising new drug used in anti-malaria combination therapy. Composed of a form of artemisinin and another highly effective medication, it also has the benefit of reduced dosage – patients take only six pills over a three-day period, compared to 24 for other therapies. This increases the chances of successful treatment, especially among young children.

Despite such progress, medical experts say the malaria crisis is not yet over for scores of nations. Dr. Awa Marie Coll-Seck is executive director of the international Roll Back Malaria Partnership.

"This is an advancement, but we cannot say that [ASAQ] it is the only drug, or just like a panacea,” she says. “It is one step forward in the right direction to help people to have access to drugs."

Dr. Coll-Seck says more new anti-malaria medications should be available soon.

"In the coming two years, we have with this Partnership around four new drugs we will be able to [bring to] the market," she says.

Malaria kills more than a million people a year. Most of the victims are children in Africa.